Compressor



p 8, 1964 B. w. HATTEN ETAL 3,147,914

COMPRESSOR Fild March 27, 1962 a 0 Mo non I Ill/l Il/N Berpdrcj W.Hcflen 8 United States Patent 3,147,914 COMPRESSOR Bernard W. Hatten andBeniarnin E. Solomon, Columbus, Ohio, assignors to Westinghouse ElectricCorporatlon, East Pittsburgh, Pa., a corporation of Pennsylvania FiledMar. 27, 1962, Ser. No. 182,369 6 Claims. (Cl. 230-232) This inventionrelates to the reduction of noise in motor-compressor units, forexample, hermetically sealed motor-compressor units for use in homerefrigerators, freezers, air conditioners, and the like.

It has heretofore been recognized that the body of oil present in thelower portion of the shell of such motorcompressor units provides asolid path for transmission to the shell of noise originating in thecompressor and that this solid path could be broken up to a considerableand worthwhile extent by generating bubbles in the oil body withconsequent reduction in the amount of noise transmitted through the oilto the lower portion of the shell. The bubbles also provide increasedabsorption (or damping) of pressure pulsation in the gas above the oilbody, thus reducing the excitation of the upper portion of the shell.

One previously used method of bubbling the oil was to discharge suctiongas into the body of oil through a perforated tube whose perforationswere below the surface of the oil body. Another such method was todisturb the oil by means of a screen kicker extending downward from theconnecting rod. This kicker also provided lubrication, and wasdistinguished by the interrupted action as it entered the oil duringonly a portion of each piston cycle.

The present invention provides a less expensive and more satisfactorymeans for producing bubbles in the body of oil and involves thedisposition of the motor rotor relative to the body of oil such that aportion of the rotor, or of structure carried by the rotor, is partiallysubmerged in the oil body. Consequently, when the motor is running, thesubmerged portion of the rotor, or of the structure carried thereby,continuously churns and aerates or gasifies the oil, producing a highdegree of bubbling or foaming of the oil, thus materially reducing thesound transmitting ability of the body of oil.

In one form of the invention the lower end ring portion of the rotorconductors is the partially submerged structure. In another form of theinvention the end ring portion of the rotor conductors is above thesurface of the body of oil, but carries downwardly extending lugs whichare partially submerged in the oil. In yet another, and preferred, formof the invention an oil stirrer of disclike shape is secured on therotor shaft just above the surface of the body of oil and has one ormore peripheral fingers or blades or other stirring members perforatedor otherwise suitable for producing bubbles extending downwardly intothe oil to agitate and foam the latter whenever the motor is running.

An object of the present invention is to reduce the transmission ofnoise from a hermetically-sealed motor-compressor unit to its sealingshell via a body of oil bridging the space between the unit and itsshell.

Another object of the invention is to continuously mechanically agitatethe body of oil in a hermetically-sealed motor-compressor unit while theunit is running.

Yet another object of the invention is to continuously stir a body ofoil in a motor-compressor unit.

The foregoing and other objects are effected by the invention as will beapparent from the following description taken in connection with theaccompanying drawings, forming a part of this application, in which:

FIG. 1 is a vertical sectional view of a motor-compressor unitincorporating oil-stirring means constructed in accordance with thepresent invention;

FIG. 2 is a fragmentary vertical sectional view of a motor-compressorunit utilizing a modified oil-stirring means of the invention;

FIG. 3 is a view similar to FIG. 2, showing yet another embodiment ofthe invention, and

FIG. 4 is a perspective view of the stirrer of FIG. 3.

As shown in FIG. 1 of the drawing, the invention is utilized in ahermetic refrigeration compressor, or motorcompressor unit, comprising atwo-part shell or case 10 having upper and lower sections 11 and 12,respectively, of sheet metal or light material which are securedtogether as by brazing, welding or other suitable means to provide ahermetically sealed joint.

The shell it houses a compressor 13 and electric motor 14 for drivingthe compressor 13. A frame 16 is provided for supporting the compressorand motor in predetermined operative relationship and includes a portion17 receiving the compressor cylinder 18 and also including amotorsupporting portion 19 having an upper half 21 which mates with alower half 22 to engage and support the motor 14. The frame halves 21and 22 may be retained in assembled relation by any suitable means, forexample, by a flange 20 on the lower half which telescopically receivesthe lower edge of the upper half 21.

A plurality of screws 23 extend through the motor stator 24 to securethe latter to the lower half 22 of the frame portion 19. A spider 25 isformed integral with the frame lower half 22 and has a central portion26 which provides a combined journal and thrust bearing for the lowerend of a vertically disposed motor shaft 27 to which is fixedly securedthe rotor 28 of the electric motor 14. The upper end of the shaft 27 isjournaled in a bearing 29 carried by the upper half 21 of the frameportion 19.

The shaft 27 includes an upwardly extending crank arm 31 disposedeccentrically with respect to the longitudinal axis of the shaft 27,this crank arm 31 carrying the free end of a connecting rod 32 throughwhich reciprocatory motion is imparted to a compressor piston 33disposed in the compressor cylinder 18.

The entire frame 16 and the motor and compressor units supported therebyare in turn supported resiliently from the shell 10 by lugs 34 integralwith the frame 16 and resting upon springs 35 which in turn rest uponlugs or brackets 36 provided on the inner side walls of the shell 10.

It will be seen that the shell 10 contains a body 38 of lubricant, as iscustomary in such hermetically sealed motor-compressor units, forlubrication of the rotating and reciprocating motor and compressor partsin a manner well known and hence not described herein.

It will be noted that in this illustrated arrangement the compressor 13is mounted above the electric motor 14 with the result that the motormay be so disposed with respect to the body 38 of lubricant in thebottom of the shell that the lower end of the rotor end ring 39 extendsbelow the surface of the body of lubricant. Consequently, during runningof the motor the submerged part of the rotor end ring 39 agitates thebody of lubricant and generates large quantities of bubbles therein toprovide the required sound deadening effect.

Referring now to the construction illustrated in FIG. 2, the generalarrangement of the motor and compressor is identical to that shown anddescribed in connection with FIG. 1 except that the lower end of therotor end ring 39 is disposed slightly above the surface of the body 38of lubricant and that the agitation of the lubricant to produce thedesired mass of bubbles is effected by the provision of one or more lugsor fingers 41 extending downwardly from the lower end ring into andbelow the surface of the lubricant.

The modification of FIGS. 3 and 4 differs from the arrangementspreviously described in connection with FIGS. 1 and 2 in that a stirrer43, preferably formed as a sheet metal stamping, is mounted on the lowerportion of the motor shaft 27 below the rotor but above the combinedthrust and journal bearing 26. This stirrer is provided with a collar 44which closely engages the shaft 27 with a press fit so that the stirrerrotates with the shaft. The

stirrer is also provided with one or more fingers 45 which project orextend downwardly into the body 38 of lubricant to agitate the latterduring operation of the motor, with the result that large quantities ofbubbles are continuously generated during motor operation to pro videthe desired sound deadening effect.

While the fingers 4.5 have been herein illustrated as lying in a circlecoaxial with the longitudinal axis of the shaft 27, it will be apparentthat the fingers may be turned slightly out of the circle to give them aworking angle or pitch to provide greater stirring or agitating actionand obviously this angle may be uniform for all of the fingers or mayvary from finger to finger both in direction and in degree. Also thecross section of each blade may be either flat or curved.

While the invention has been shown in several forms, it will be obviousto those skilled in the art that it is not so limited, but issusceptible of various other changes and modifications without departingfrom the spirit thereof.

What is claimed is:

1. In refrigeration apparatus,

a gas-containing shell,

a motor-compressor unit mounted within said shell in spaced relation tothe latter,

a body ofoil within said shell,

said motor-compressor unit including a motor rotor rotatable about avertical axis, and a motor stator extending into the body of oil fortransfer of heat from the motor to the oil,

a motor-compressor shaft mounted within said rotor,

the lower end of said rotor being disposed in said body of oil, wherebyduring rotation the oil is foamed thereby reducing sound transmissiontherethrough from the motor-compressor unit to the shell.

2. In refrigeration apparatus,

a gasscontaining shell,

a motor-compressor unit resiliently mounted within said shell in spacedrelation to the latter,

a bodyjof oil within said shell, said motor-compressor unit includingamotor stator extending into the body 7 of oil for transfer of heat fromthe motor to the oil,

a motor rotor rotatable about a vertical axis,

a shaft mounted within. said rotor, and

a lug depending from the rotor into the body of oil for agitating theoil to produce foaming of the latrter, thereby reducing the transmissionof sound therethr-ough from the motor-compressor unit to the she 1.

3. In refrigeration apparatus,

a gas-containing shell,

a motor-compressor unit resiliently mounted Within said shell in spacedrelation to the latter,

a body of oil within said shell, said motor-compressor unit including amotor stator extending into the body of oil for transfer of heat fromthe motor to the oil,

a motor rotor core rotatable about a vertical axis and spaced from thebody of oil,

a compressor shaft mounted in said rotor core, and

a lug depending from said rotor core into said body of oil for agitatingthe latter to produce foaming thereof, thereby reducing transmission ofsound therethrough from the motor-compressor unit to the shell.

4-. In refrigeration apparatus,

a gas-containing shell,

a body of oil in said shell,

a motor-compressor unit mounted within said shell in spaced relation tothe latter with the motor of said unit disposed below the compressorthereof, said motor having a stator extending into the body of oil fortransfer of heat from the motor to the oil,

a rotor, a shaft mounted in said rotor and rotatable about a verticalaxis, and said rotor including a member extending downwardly into saidbody of oil for agitating the latter to produce foaming thereof, wherebytransmission of sound therethrough from the motor-compressor unit to theshell is reduced.

5. In refrigeration apparatus,

a gas-containing shell,

2. body of oil in said shell,

a motor-compressor unit resiliently mounted within said shell in spacedrelation to the latter with the motor of said unit disposed below thecompressor thereof, said motor having a stator extending into the bodyof oil for transfer of heat from the motor to the oil,

a rotor,

a shaft mounted in said rotor and rotatable about a vertical axis, saidrotor having a lug projecting downwardly therefrom into said body of oilfor agitating the latter to produce foaming thereof, thereby reducingtransmission of sound from the motor-compressor unit to the shell viathe body of oil.

6. In refrigeration apparatus,

a gas-containing shell,

a body of oil insaid shell,

a motor-compressor unit resiliently mounted within said shell in spacedrelation to the latter with the motor of said'unit disposed below thecompressor thereof, said motor including a stator extending into thebody of oil for transfer of heat from the motor to the oil,

a shaft rotatable about a vertical axis, and

a stirrer secured to the lower terminal portion of said shaft androtatable therewith, said stirrer including a plurality of lugsextending into said body of oil for agitating the latter to effectfoaming thereof, said lugs lying in planes generally tangential to acircle concentric with the axis of rotation of said shaft.

References Cited in the file of this patent UNITED STATES PATENTS2,199,415 Philipp May 7, 1940 2,990,111 Bohn June 27, 1961 2,996,240Stocklein et al. Aug. 15, 1961

1. IN REFRIGERATION APPARATUS, A GAS-CONTAINING SHELL, AMOTOR-COMPRESSOR UNIT MOUNTED WITHIN SAID SHELL IN SPACED RELATION TOTHE LATTER, A BODY OF OIL WITHIN SAID SHELL, SAID MOTOR-COMPRESSOR UNITINCLUDING A MOTOR ROTOR ROTATABLE ABOUT A VERTICAL AXIS, AND A MOTORSTATOR EXTENDING INTO THE BODY OF OIL FOR TRANSFER OF HEAT FROM THEMOTOR TO THE OIL, A MOTOR-COMPRESSOR SHAFT MOUNTED WITHIN SAID ROTOR,THE LOWER END OF SAID ROTOR BEING DISPOSED IN SAID BODY OF OIL, WHEREBYDURING ROTATION THE OIL IS FOAMED THEREBY REDUCING SOUND TRANSMISSIONTHERETHROUGH FROM THE MOTOR-COMPRESSOR UNIT TO THE SHELL.